SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97271885ee7b865835c832b713de9b7506958485b8283a11739346914d74075a' 
  AND token = '+5rEligcjbDnz+/aYZsZX+r6CxgS+ZOfZjmVQJrHHqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}